1. Field of the Invention
This invention relates to a method of achieving an improved fuel composition and simultaneously recovering valuable chemical products. More particularly, this invention relates to a method of effecting a low-sulfur, low-ash coal that burns readily with high efficiency and low pollution emissions; and, simultaneously recovering, by dissolution from the coal, valuable chemical products.
2. Description of Prior Art
In my earlier filed and co-pending application Ser No. 615,697, entitled "Fuel Composition and Method of Manufacture," filed Sept. 22, 1975, there was delineated the need for obtaining economical power, yet balancing the ecological considerations so as to achieve an overall improvement of our environment, reduce pollution and the like. The latter is made more difficult by the so called "energy shortage;" evidenced by curtailment of deliveries and then only at higher prices, of natural gas, gasoline and other petroleum products.
An excellent discussion of these conventional sources of power and their shortcomings is contained in an article, "Hydrogen; Its Future in the Nation's Energy Economy," W. E. Winsche, K. C. Hoffman, and F. J. Salzano, SCIENCE, June 29, 1973, Vol. 180, No. 4093. Therein, the authors delineate the projected need for large scale economical sources of energy, such as that derived from nuclear fission, solar or geothermal sources. In that article, the authors point out the disadvantages of several conventional sources of power and extoll the virtues of hydrogen as a potential future fuel, since it is non-polluting.
It is becoming increasingly apparent that certain oil-rich areas of the earth may be able to exert a dis-proportionately large economical and political influence if the substitute is not found for the petroliferous fuels. One widely available substitute for the petroliferous fuels is coal. Frequently, however, the coal contains sulfur, ash-producing minerals and other pollutants that make it objectionable, or make prohibitive (or at least economically infeasible) the cost of treating the coal to remove the pollutants when employed in populous areas. Moreover, the costs of mining and transporting coal over long distances have made it noncompetitive with crude oil heretofore, since crude oil was available at a cost of about $3.00 a barrel. As crude oil increases in cost to $5.00 a barrel or higher, coal becomes increasingly competitive as a source of fuel. It could be particularly competitive if a way could be found to transport the coal economically. For example, coal provides energy at the cost of about twenty cents per million British Thermal Units (BTU's). Large reserves of coal are available in the United States, notably, in Alaska, Wyoming, Utah, the central States and the lignite deposits in Texas. As indicated, transportation of coal has required a disproportionately large amount of trouble and expense.
In the hereinbefore referenced application Ser. No. 615,697, there is described a portion of the proposals that have been tried heretofore to solve the transportation problem and there is disclosed the improved process that obviates the disadvantages of the prior art. That application did not, however, reduce the sulfur by-product producing or ash producing content of the coal or recover valuable chemicals as side products.
Thus, it can be seen that the prior art has not been totally satisfactory in providing a low-sulfur, low-ash fuel from coal, and simultaneously recovering valuable chemical products.